Warning system and device, and malodorous warning composition of matter and process for its preparation

ABSTRACT

The malodorous warning composition of matter includes the ingredients of a liquid mercaptan mixed with a nonflammable solvent having a relatively low vapor pressure, such as trichloromonofluoremethane, and an inert gas such as nitrogen under pressure, to form a malodorous mixture for introduction into pressurized air breathing systems, such as for mines, to warn a person of danger by the odor. This new composition of matter has no need for external means of heating or cooling the mixture for introducing it into the pressurized air breathing system. The process for its preparation includes the steps of introducing an inert gas under pressure into a suitable container in which the mercaptan and solvent have been previously placed, and producing a pressure internally of about 250 to 300 pounds per square inch, and sealing the container by a needle valve or other suitable means. The warning device includes the malodorous composition of matter together with a suitable high pressure container equipped with a high pressure needle valve. The warning system includes the warning device together with an adapter on the end of the needle valve, to which is connected a feeder tube means having a fitting or coupling for connection of its outer end to a valve of its outer end to a valve of a pressurized air breathing system of a facility such as a mine.

United States Patent Selleck Jan. 21,1975

[ WARNING SYSTEM AND DEVICE, AND

MALODOROUS WARNING COMPOSITION OF MATTER AND PROCESS FOR ITS PREPARATION Albert B. Selleck, 19310 Caladero St., Tarzana, Calif. 91356 22 Filed: Apr. 20, 1973 21 Appl. No.: 353,491

Related U.S. Application Data [62] Division of Ser. No. 165,537, July 23, 1971, Pat. No.

[76] Inventor:

[52] U.S. Cl 116/114, 48/195, 98/50 [51] Int. Cl. G01d 21/00 [58] Field of Search 98/50; 48/195; 252/305, 252/408; 116/114 [56] References Cited UNITED STATES PATENTS 2,894,478 7/1959 Reed et al 48/195 3,387,425 6/1968 Flanner 3,475,146 10/1969 Olund 252/408 Primary ExaminerS. Clement Swisher Attorney, Agent, or Firm-John Joseph Hall [57] ABSTRACT The malodorous warning composition of matter includes the ingredients of a liquid mercaptan mixed with a nonflammable solvent having a relatively low vapor pressure, such as trichloromonofluoremethane, and an inert gas such as nitrogen under pressure, to form a malodorous mixture for introduction into pressurized air breathing systems, such as for mines, to warn a person of danger by the odor. This new composition of matter has no need for external means of heating or cooling the mixture for introducing it into the pressurized air breathing system.

The process for its preparation includes the steps of introducing an inert gas under pressure into a suitable container in which the mercaptan and solvent have been previously placed, and producing a pressure internally of about 250 to 300 pounds per square inch, and sealing the container by a needle valve or other suitable means.

The warning device includes the malodorous composition of matter together with a suitable high pressure container equipped with a high pressure needle valve. The warning system includes the warning device together with an adapter on the end of the needle valve, to which is connected a feeder tube means having a fitting or coupling for connection of its outer end to a valve of its outer end to a valve of a pressurized air breathing system of a facility such as a mine.

11 Claims, 1 Drawing Figure WARNING SYSTEM AND DEVICE, AND MALODOROUS WARNING COMPOSITION OF MATTER AND PROCESS FOR ITS PREPARATION This is a division of application Ser. No. 165,537, filed July 23, 1971, now US. Pat. No. 3,767,591

BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a malodorous composition of matter for introduction into a pressurized air breathing system, such as those used for mines, to warn a person of danger by the malodorous smell. The process for its preparation involves the mixing of a mercaptan with a nonflammable solvent with a relatively low vapor pressure over a wide range of temperatures and subjecting the resulting mixture with an inert gas under pressure for expelling the composition of matter into a pressurized air breathing system.

The invention also includes the combination of a malodorous composition of matter with a suitable high pressure container equipped with a high pressure needle valve, to form a warning device. The invention also includes a mine warning system when the warning device is equipped with an adapter connected to a tube means leading to a valve of a pressurized air breathing system of the desired facility.

2. Prior art Applicant knowns of no prior art making use of the particular combination of ingredients disclosed in this application, or of a process for its preparation as described herein, or a combination of such ingredients together with a high pressure container and needle valve, or additionally of an adapter and feeder tube means.

SUMMARY OF THE INVENTION The malodorous composition of matter has three basic ingredients: a mercaptan, to produce the warning odor; a solvent for the mercaptan, which serves to reduce the flammability and explosive qualities of the mercaptan by acting as a diluent and nonflammable solvent medium; and an inert gas under pressure to force the composition of matter from a high pressure container into the pressurized air breathing system.

For relative ease in preparing the malodorous composition of matter, a liquid mercaptan at ambient temperatures is preferred. Such mercaptans include methyl mercaptan, ethyl mercaptan, both n-propyl and isopropyl mercaptan, referred to hereinafter as propyl mercaptan, both secondary and tertiary butyl mercaptan, both referred to hereinafter as buty] mercaptan, and tetrahydrothiophene, referred to hereinafter as thiophane.

Other suitable malodorous compounds for this composition of matter include dimethyl sulfide, and ethyl iso-propyl sulfide.

Since all ofthese compounds are flammable or explosive or both, it is highly desirable to incorporate them into a nonflammable solvent for safety and ease in handling and application. Such a solvent must also have a relatively low vapor pressure over a relatively wide temperature range, which may be defined as a maximum vapor pressure of not over 40 pounds per square inch at 1 atmosphere, i.e., sea level, at a maximum temperature of 130 F. Such suitable solvents are trichloromonofluoromethane, trichlorotrifluorethane, 111- trichlorethane, also known as methylchloroform, methylene chloride, trichloroethylene, and perchloroethylene.

Since the vapor pressure at sea level of these solvents is lowered as the temperature is decreased below the maximum temperature of degrees Fahrenheit the only limitation as to cold temperatures is the effectiveness of the inert gas under pressure to expel the composition of matter from the container into the pressurized air breathing system.

The usual pressurized air breathing system for mines in the United States averages about pounds per square inch, with respect to the amount of pressure used. So long as the internal pressure in the container holding the malodorous composition of matter exceeds 150 pounds per square inch, no difficulty exists in using the warning mixture.

Nitrogen gas is a particularly suitable inert gas for use in preparing the malodorous composition of matter. When the container has been charged with nitrogen gas to an internal pressure of about 275 pounds per square inch at room temperatures, sufficient pressure exists to expel the contents of the container at temperatures as low as 30 F. into pressurized air breathing systems maintained at a pressure of 150 pounds per square inch. Also, the increase in internal pressure of such a container, thus charged with nitrogen gas, at a temperature of 130 F. is insufficient to burst the standard high pressure cylinder used as a container for the malodorous composition of matter.

Various other inert gases having similar characteristics as nitrogen gas may also be used. For example, carbon dioxide gas or nitrous oxide gas may be used without adversely affecting the results obtained by my invention.

Once the malodorous composition of matter has been prepared under the desired pressure in a high pressure container, the container may be stored for an indefinite period of time without adversely affecting the operation of my invention. Moreover, when the container is to be employed, it may be used without any other preparation of heating or cooling of the contents, before introducing the contents into a pressurized air breathing system.

The container is preferably a high pressure cylinder capable of withstanding up to 375 pounds per square inch pressure or more at sea level, and equipped with a high pressure needle valve having a corrosion resistant seat of Teflon or other suitable material. The container and valve, together with the malodorous composition of matter, make up the mine warning device.

When the warning device is equipped further with an adapter and feeder tube means, for attachment to a valve of a pressurized air breathing system for a facility such as a mine, the invention then becomes a warning system.

It is, therefore, an object of this invention to provide a malodorous warning composition of matter which is relatively easy to prepare and to store for long periods of time without deterioration or special handling.

Another object of this invention is to provide a malodorous warning composition of matter which can be contained in a high pressure cylinder and used immediately over a range of temperatures from about 10 F. to about 130 F. without the necessity for heating or cooling the container or its contents.

A further object of this invention is to provide a malodorous warning composition of matter which can be prepared from readily available materials and at a relatively inexpensive cost.

A still further object of this invention is to provide a malodorous warning composition of matter which is relatively safe to use both from the aspect of being relatively nontoxic and relatively nonflammable.

A yet another object of this invention is to provide a warning device capable of containing said malodorous composition of matter under pressure and of permitting said composition of matter to escape through a valve means.

A yet further object of this invention is to provide a warning system having the capability of containing and delivering said malodorous composition of matter under pressure when desired into a pressurized air breathing system of a facility such as a mine, over a range of temperatures from about F. to about 130 F., without the necessity for heating or cooling the container of the warning system or its contents.

These and other objects will be more readily understood by reference to the following specification and claims, takine in conjunction with the accompanying drawing, in which FIG. I is a side elevational view of the invention in position for introducing the malodorous composition of matter into a pressurized air breathing system of a facility, said air breathing system being shown in part and by dotted lines.

DESCRIPTION OF PREFERRED EMBODIMENTS The warning device 10 has a high pressure cylinder 12 with an internal capacity of about 75 cubic inches. One end ofthe cylinder 12 is equipped with a high pressure needle valve 14 with a handle 15 to open and close the valve 14. Preferably, the valve 14 is equipped with a corrosion resistant seat made of Teflon or other corrosion resistant material. An adapter 16 is attached to the outer end of the valve 14.

The malodorous warning composition of matter 18 included and contained in the warning device 10 occupies only part of the interior of the cylinder 12, the rest being taken up by the compressed inert gas 20.

Warning system 22 includes warning device 10 with malodorous composition of matter 18 and compressed inert gas 20, together with feeder tube 24 having a flared threaded fitting 26 connected to adapter 16 at one end, and having a similar flared threaded fitting 27 at its other end connected to adapter 28 threaded on pipe nipple 29 of valve 30 opening into the pressurized air breathing system 32 of the facility, shown in part and by dotted lines in the drawing. Various alternative connecting means may be used.

The same general procedure is used in the preparation of the malodorous warning composition of matter, regardless of the various ingredients used in each of the three categories making up the malodorous warning composition of matter the substance producing the warning odor, the solvent, and the inert gas. Although not essential, I have found it preferable to add an additional step in the preparation of the malodorous composition of matter of agitating the contents of the container after being charged with the inert gas, and then re-charging the container to allow for a decrease in internal pressure due to the partial absorption of the inert gas under pressure by the liquid contents. In this manner, a uniform internal pressure may be achieved and maintained inside the container.

EXAMPLE 1 The preparation of the malodorous composition of matter may be accomplished at ambient temperatures such as room temperature of about F. or at other convenient ambient temperatures.

About 100 grams of ethyl mercaptan is placed inside a cylinder 12 capable of withstanding relatively high internal pressure such as 300 to 350 pounds per square inch at sea level and equipped with a high pressurc needle valve 14. A suitable internal capacity of the cylinder is about cubic inches.

Next, about 450 grams of solvent. trichloromonofluoromethane is added to the grams of ethyl mercaptan inside the cylinder.

Then, sufficient nitrogen gas under pressure is introduced through the needle valve 14 into the cylinder 12 to produce an internal pressure of about 275 pounds per square inch inside the cylinder 12 at ambient temperatures.

Optionally, and preferably, the cylinder 12 is then agitated for a minimum period of time of about 30 seconds to mix the liquid contents thoroughly inside the cylinder 12 and to complete whatever absorption may occur of the inert nitrogen gas by the mixture of ethyl mercaptan and trichloromonofluoromethane solvent. Such absorption may vary from 3 to 6 per cent by weight of the nitrogen gas and may lower the initial internal pressure of the cylinder 12 from about 275 pounds per square inch to about 240 to 245 pounds per square inch. Since such lower pressures are more than ample for introduction of the malodorous composition of matter into conventional pressurized air breathing systems of about pounds per square inch in the United States, re-charging of the cylinder 12 with nitrogen gas back up to the initial internal pressure of about 275 pounds per square inch is not actually necessary.

To maintain uniformity of pressure, however, additional nitrogen gas under pressure is introduced through the needle valve 14 of the cylinder 12 until the initial internal pressure of 275 pounds per square inch is restored, as indicated by the pressure neutralization gauge of a nitrogen gas reservoir tank.

The needle valve 14 is then closed and capped with a safety cap for storage purposes. The charged cylinder may then be stored as needed without any special precautions of location or of ambient temperatures.

In the example given above, the amount of nitrogen gas by weight to maintain an internal pressure of about 275 pounds per square inch after agitation of the cylinder 12, is about 30 grams by weight at ambient temperatures.

In use, the warning device 10 is placed in a vertical position with its needle valve 14 at the bottom. The safety cap (not shown), if on the needle valve 14, is removed. Fitting 26 of feeder tube 24 is connected to the adapter 16 on the outer end of the needle valve 14 and fitting 27 on the other end of feeder tube 24 is isconnected by adapter 28 to pipe nipple 29 of valve 30 of the pressurized air breathing system 32 of the facility.

The warning system 22 is now ready for introduction into the pressurized air breathing system 32 of the malodorous warning composition of matter. The handle 15 of the valve 16 is turned all the way open. Due to the substantial excess in pressure of the contents of the cylinder 12 over the prevailing pressure in the pressuring air breathing system 32, the entire liquid contents l8 and a substantial part of the inert gas 20 are exhausted into the pressurized air breathing system 32 is about 5 seconds, until the remaining inert gas in the cylinder 12 reaches an equilibrium pressure with the pressure of the pressurized air breathing system 32.

Valve 30 of the pressurized air breathing system 32 is then closed, and the warning system 22 is then removed from its connection with the pressurized air breathing system 32.

If desired, the cylinder 12 may be disposed of, or reused as part of another warning device and warning system 22. Due to the novel features of my invention, the warning system 22 is fully effective at ambient temperatures ranging from a minimum of about 10 F. to

about 130 F. without any heating or cooling of the cyll inder l2, and without any special preparation, where the pressurized air breathing system of the mine or other facility is at a pressure of about 150 pounds per square inch.

EXAMPLE 2 The steps of Example 1 are repeated with the substitution of about 100 grams of methyl mercaptan instead of ethyl mercaptan and the same results are obtained.

EXAMPLE 3 The steps of Example 1 are repeated with the substitution of about 450 grams oftrichlorotrifluorethane instead of the trichloromonofluoromethane and the same results are obtained.

EXAMPLE 4 The steps of Example 2 are repeated with the substitution of about 450 grams of trichlorotrifluorethane instead of the trichloromonofluoromethane and the same results are obtained.

The ratio of parts by weight ofthe liquid malodorous substance and the solvent may vary from 1 part of the former to 2 parts of the latter, as a maximum, to about 1 part of the former to about 6 parts ofthe latter, without adversely affecting the results. Also, the amount of inert gas may vary from .2 to .4 parts by weight where the ratio of liquid malodorous substance and solvent is l: 2 and l: 6 respectively, thereby producing a variance in internal pressure of a 75 cubic inch high pressure cylinder from about 200 pounds per square inch to about 430 pounds per square inch at room temperatures of about 70 F. without adversely affecting the results. Of course, for the higher pressures, suitable high pressure cylinders must be used that are capable of withstanding such higher pressures.

If it is desired to use high pressure cylinders of greater or lesser capacity than 75 cubic inches internally, the various amounts of ingredients can be adjusted in proportion to the increased or diminished capacity of the cylinder so that effective operating pressures may be obtained internally over the temperature range of l0 to 130 F. The higher internal pressures. i.e., over 275 pounds per square inch. may be effectively used where the expected operating temperatures are below 30 F. The only essential requirement for operation of my invention is that the internal pressure of the charged cylinder be in excess of the pressures used in the pressurized air breathing system of the particular facility where the malodorous warning composition of matter is to be introduced.

Although I have described preferred embodiments of my invention, it is understood that the scope of the invention is not limited thereby, but numerous variations in ingredients and procedures are possible without departing from the spirit and scope of the invention claimed hereinafter.

I claim:

1. A warning system for introducing a malodorous composition of matter into a pressurized air breathing system of a facility to provide a warning odor to a person in case of danger, said pressurized air breathing system having a minimum pressure of about 150 pounds per square inch, comprising:

a high pressure container equipped with a valve means at one end;

connecting means connecting said valve means ofthe container to valve means of a pressurized air breathing system of a facility;

about 1 part by eight of a liquid malodorous substance inside said container;

from about 2 to about 6 parts by weight ofa nonflammable solvent for said liquid malodorous substance, said solvent having a maximum vapor pressure of less than 40 pounds per square inch at sea level at a temperature of about F., inside said container; and

from about .2 to about .4 parts by eight of an inert gas uner pressure inside said container, whereby a pressure of at least 200 pounds per square inch is produced inside said high pressure container over a temperature range of from about 10 to about 130 F.

2. A warning system according to claim 1 in which the liquid malodorous substance is selected from the group consisting of methyl mercaptan, ethyl mercaptan, propyl mercaptan, butyl mercaptan, and thiphane.

3. A warning system according to claim 1 in which the liquid malodorous substance is a mercaptan which is a liquid at ambient temperatures.

4. A warning system according to claim 1 in which the liquid malodorous substance is dimethyl sulfide.

5. A warning system according to claim 1 in which the liquid malodorous substance is ethyl iso-propyl sulfide.

6. A warning system according to claim 1 in which the solvent is selected from the group consisting of trichloromonofluoromethane, trichlorotrifluoroethane lll-trichloroethane, methylene chloride, and trichloroethylene.

7. A warning system for introducing a malodorous composition of matter into a pressurized air breathing system of a facility to provide a warning odor to a person in case of danger, said pressurized air breathing system having a minimum pressure of about pounds per square inch, comprising:

a high pressure cylinder equipped with high pressure needle valve means at one end; connecting means connecting said needle valve means of the high pressure cylinder to valve means of a pressurized air breathing system of a facility;

about 1 part by weight of a liquid malodorous substance inside said cylinder;

from about 2 to about 6 parts by weight ofa nonflammable solvent for said liquid malodorous substance, said solvent having a maximum vapor pressure of less than 40 pounds per square inch at sea level at a temperature of about 130 F., inside said cylinder; and

from about .2 to about .4 parts by eight of an inert gas selected from the group consisting of nitrogen, carbon dioxide, and nitrous oxide, under pressure inside said cylinder, whereby a pressure of at least 200 pounds per square inch is produced inside said high pressure container over a temperature range of from about l to about 13 F.

8. A warning system according to claim 7 in which the liquid malodorous substance is selected from the group consisting of methyl mercaptan, ethyl mercaptan, propyl mercaptan, butyl mercaptan, and thioin which the solvent is trichloromonofluoromethane. 

1. A WARNING SYSTEM FOR INTRODUCING A MALODOROUS COMPOSITION OF MATTER INTO A PRESSURIZED AIR BREATHING SYSTEM OF A FACILITY TO PROVIDE A WARNING ODOR TO A PERSON IN CASE OF DANGER, SAID PRESSURIZED AIR BREATHING SYSTEM HAVING A MINIMUM PRESSURE OF ABOUT 150 POUNDS PER SQUARE INCH, COMPRISING: A HIGH PRESSURE CONTAINER EQUIPPED WITH A VALVE MEANS AT ONE END; CONNECTING MEANS CONNECTING SAID VALVE MEANS OF THE CONTAINER TO VALVE MEANS OF A PRESSURIZED AIR BREATHING SYSTEM OF A FACILITY; ABOUT 1 PART BY EIGHT OF A LIQUID MALODOROUS SUBSTANCE INSIDE SAID CONTAINER; FROM ABOUT 2 TO ABOUT 6 PARTS BY WEIGHT OF A NONFLAMMABLE SOLVENT FOR SAID LIQUID MALODOROUS SUBSTANCE, SAID SOLVENT HAVING A MAXIUM VAPOR PRESSURE OF LESS THAN 40 POUNDS PER SQUARE INCH AT SEA LEVEL AT A TEMPERATURE OF ABOUT 130*F., INSIDE SAID CONTAINER;AND FROM ABOUT .2 TO ABOUT .4 PARTS BY EIGHT OF AN INERT GAS UNDER PRESSURE INSIDE SAID CONTAINER, WHEREBY A PRESSURE OF AT LEAST 200 POUNDS PER SQUARE INCH IS PRODUCED INSIDE SAID HIGH PRESSURE CANTAINER OVER A TEMPERATURE RANGE OF FROM ABOUT 10* TO ABOUT 130*F.
 2. A warning system according to claim 1 in which the liquid malodorous substance is selected from the group consisting of methyl mercaptan, ethyl mercaptan, propyl mercaptan, butyl mercaptan, and thiphane.
 3. A warning system according to claim 1 in which the liquid malodorous substance is a mercaptan which is a liquid at ambient temperatures.
 4. A warning system according to claim 1 in which the liquid malodorous substance is dimethyl sulfide.
 5. A warning system according to claim 1 in which the liquid malodorous substance is ethyl iso-propyl sulfide.
 6. A warning system according to claim 1 in which the solvent is selected from the group consisting of trichloromonofluoromethane, trichlorotrifluoroethane 111-trichloroethane, methylene chloride, and trichloroethylene.
 7. A warning system for introducing a malodorous composition of matter into a pressurized air breathing system of a facility to provide a warning odor to a person in case of danger, said pressurized air breathing system having a minimum pressure of about 150 pounds per square inch, comprising: a high pressure cylinder equipped with high pressure needle valve means at one end; connecting means connecting said needle valve means of the high pressure cylinder to valve means of a pressurized air breathing system of a facility; about 1 part by weight of a liquid malodorous substance inside said cylinder; from about 2 to about 6 parts by weight of a nonflammable solvent for said liquid malodorous substance, said solvent having a maximum vapor pressure of less than 40 pounds per square inch at sea level at a temperature of about 130* F., inside said cylinder; and from about .2 to about .4 parts by eight of an inert gas selected from the group consisting of nitrogen, carbon dioxide, and nitrous oxide, under pressure inside said cylinder, whereby a pressure of at least 200 pounds per square inch is produced inside said high pressure container over a temperature range of from about 10* to about 13* F.
 8. A warning system according to claim 7 in which the liquid malodorous substance is selected from the group consisting of methyl mercaptan, ethyl mercaptan, propyl mercaptan, butyl mercaptan, and thiophane.
 9. A warning system according to claim 7 in which the solvent is selected from the group consisting of trichloromonofluoromethane, trichlorotrifluoroethane, 111-trichloroethane, methylene chloride, and trichloroethylene.
 10. A warning system according to claim 7 in which the liquid malodorous substance is a mercaptan which is a liquid at ambient temperatures.
 11. A warning system according to claim 7 in which the liquid malodorous substance is ethyl mercaptan and in which the solvent is trichloromonofluoromethane. 